Apps can't connect to smart device

Hello,

I have an issue with.. well I don't know with what.

I have a cheap Chinese camera and one day I see that it is gone from my app. You send Wifi info to camera via phone and when camera gets wifi it connects to app. So I reset the cam and send Wifi pass to it, it connected to WiFi, but my phone said fail to connect and that's it. But camera has a wifi light on and if I turn off the router the light goes off and when wifi on it comes back again.

So I thought it's an app or device fault. Now I bought new AEG dryer with wifi function and it's exactly the same. Phone is searching for device, asks for wifi pass, sends the info dryer connects to WiFi, strength 5/5, ip matches and all but app still tries to connect it and after 5- 10min I get an error message. This message is attached.

No idea what to do, I already tried with: Poco f1, Huawei p10, Huawei P9 lite 2019

Any ideas?